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select_feature_set_trainf_svmT_select_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm (Operator)

Name

select_feature_set_trainf_svmT_select_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm — Selects an optimal combination of features to classify OCR data.

Signature

select_feature_set_trainf_svm( : : TrainingFile, FeatureList, SelectionMethod, Width, Height, GenParamName, GenParamValue : OCRHandle, FeatureSet, Score)

Herror T_select_feature_set_trainf_svm(const Htuple TrainingFile, const Htuple FeatureList, const Htuple SelectionMethod, const Htuple Width, const Htuple Height, const Htuple GenParamName, const Htuple GenParamValue, Htuple* OCRHandle, Htuple* FeatureSet, Htuple* Score)

Herror select_feature_set_trainf_svm(const HTuple& TrainingFile, const HTuple& FeatureList, const HTuple& SelectionMethod, const HTuple& Width, const HTuple& Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* OCRHandle, HTuple* FeatureSet, HTuple* Score)

HTuple HOCRSvm::SelectFeatureSetTrainfSvm(const HTuple& TrainingFile, const HTuple& FeatureList, const HTuple& SelectionMethod, const HTuple& Width, const HTuple& Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* Score)

void SelectFeatureSetTrainfSvm(const HTuple& TrainingFile, const HTuple& FeatureList, const HTuple& SelectionMethod, const HTuple& Width, const HTuple& Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* OCRHandle, HTuple* FeatureSet, HTuple* Score)

HTuple HOCRSvm::SelectFeatureSetTrainfSvm(const HTuple& TrainingFile, const HTuple& FeatureList, const HString& SelectionMethod, Hlong Width, Hlong Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* Score)

HTuple HOCRSvm::SelectFeatureSetTrainfSvm(const HString& TrainingFile, const HString& FeatureList, const HString& SelectionMethod, Hlong Width, Hlong Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* Score)

HTuple HOCRSvm::SelectFeatureSetTrainfSvm(const char* TrainingFile, const char* FeatureList, const char* SelectionMethod, Hlong Width, Hlong Height, const HTuple& GenParamName, const HTuple& GenParamValue, HTuple* Score)

void HOperatorSetX.SelectFeatureSetTrainfSvm(
[in] VARIANT TrainingFile, [in] VARIANT FeatureList, [in] VARIANT SelectionMethod, [in] VARIANT Width, [in] VARIANT Height, [in] VARIANT GenParamName, [in] VARIANT GenParamValue, [out] VARIANT* OCRHandle, [out] VARIANT* FeatureSet, [out] VARIANT* Score)

VARIANT HOCRSvmX.SelectFeatureSetTrainfSvm(
[in] VARIANT TrainingFile, [in] VARIANT FeatureList, [in] BSTR SelectionMethod, [in] Hlong Width, [in] Hlong Height, [in] VARIANT GenParamName, [in] VARIANT GenParamValue, [out] VARIANT* Score)

static void HOperatorSet.SelectFeatureSetTrainfSvm(HTuple trainingFile, HTuple featureList, HTuple selectionMethod, HTuple width, HTuple height, HTuple genParamName, HTuple genParamValue, out HTuple OCRHandle, out HTuple featureSet, out HTuple score)

HTuple HOCRSvm.SelectFeatureSetTrainfSvm(HTuple trainingFile, HTuple featureList, string selectionMethod, int width, int height, HTuple genParamName, HTuple genParamValue, out HTuple score)

HTuple HOCRSvm.SelectFeatureSetTrainfSvm(string trainingFile, string featureList, string selectionMethod, int width, int height, HTuple genParamName, HTuple genParamValue, out HTuple score)

Description

select_feature_set_trainf_svmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm selects an optimal combination of features, to classify the data given in the training file TrainingFileTrainingFileTrainingFileTrainingFileTrainingFiletrainingFile with a Support Vector Machine (SVM), for details see create_ocr_class_svmcreate_ocr_class_svmCreateOcrClassSvmcreate_ocr_class_svmCreateOcrClassSvmCreateOcrClassSvm.

Possible features are all OCR features listed and explained in create_ocr_class_svmcreate_ocr_class_svmCreateOcrClassSvmcreate_ocr_class_svmCreateOcrClassSvmCreateOcrClassSvm. All candidates which should be tested can be specified in FeatureListFeatureListFeatureListFeatureListFeatureListfeatureList. A subset of these features is returned as selected features in FeatureSetFeatureSetFeatureSetFeatureSetFeatureSetfeatureSet.

select_feature_set_trainf_svmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm is specialized on OCR problems and only supports the features in the list mentioned before. In order to use other features, please use the more general operator select_feature_set_svmselect_feature_set_svmSelectFeatureSetSvmselect_feature_set_svmSelectFeatureSetSvmSelectFeatureSetSvm.

The selection method SelectionMethodSelectionMethodSelectionMethodSelectionMethodSelectionMethodselectionMethod is either a greedy search 'greedy'"greedy""greedy""greedy""greedy""greedy" (iteratively add the feature with highest gain) or the dynamically oscillating search 'greedy_oscillating'"greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating" (add the feature with highest gain and test then if any of the already added features can be left out without great loss). The method 'greedy'"greedy""greedy""greedy""greedy""greedy" is generally preferable, since it is faster. Only in cases when a large training set is available the method 'greedy_oscillating'"greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating" might return better results.

The optimization criterion is the classification rate of a two-fold cross-validation of the training data. The best achieved value is returned in ScoreScoreScoreScoreScorescore.

The parameters 'nu'"nu""nu""nu""nu""nu" and 'gamma'"gamma""gamma""gamma""gamma""gamma" for the SVM that is used to classify can be set to 'auto'"auto""auto""auto""auto""auto" by using the parameters GenParamNameGenParamNameGenParamNameGenParamNameGenParamNamegenParamName and GenParamValueGenParamValueGenParamValueGenParamValueGenParamValuegenParamValue. If they are set to 'auto'"auto""auto""auto""auto""auto", the estimated optimal 'nu'"nu""nu""nu""nu""nu" and/or 'gamma'"gamma""gamma""gamma""gamma""gamma" is estimated. The automatic estimation of 'nu'"nu""nu""nu""nu""nu" and 'gamma'"gamma""gamma""gamma""gamma""gamma" can take a substantial amount of time (up to days, depending on the data set and the number of features). Alternatively, a certain value for both can be set the same way. An explanation of the parameters 'nu'"nu""nu""nu""nu""nu" and 'gamma'"gamma""gamma""gamma""gamma""gamma" as the kernel parameter of the radial basis function (RBF) kernel can be found in create_class_svmcreate_class_svmCreateClassSvmcreate_class_svmCreateClassSvmCreateClassSvm.

Attention

This operator may take considerable time, depending on the size of the data set in the training file, and the number of features.

Please note, that this operator should not be called, if only a small set of training data is available. Due to the risk of overfitting the operator select_feature_set_trainf_svmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm may deliver a classifier with a very high score. However, the classifier may perfom poorly when tested.

Parallelization

This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.

Parameters

TrainingFileTrainingFileTrainingFileTrainingFileTrainingFiletrainingFile (input_control)  filename.read(-array) → HTupleHTupleHTupleVARIANTHtuple (string) (string) (HString) (char*) (BSTR) (char*)

Names of the training files.

Default value: '' "" "" "" "" ""

File extension: .trf, .otr

FeatureListFeatureListFeatureListFeatureListFeatureListfeatureList (input_control)  string(-array) → HTupleHTupleHTupleVARIANTHtuple (string) (string) (HString) (char*) (BSTR) (char*)

List of features that should be considered for selection.

Default value: ['zoom_factor','ratio','width','height','foreground','foreground_grid_9','foreground_grid_16','anisometry','compactness','convexity','moments_region_2nd_invar','moments_region_2nd_rel_invar','moments_region_3rd_invar','moments_central','phi','num_connect','num_holes','projection_horizontal','projection_vertical','projection_horizontal_invar','projection_vertical_invar','chord_histo','num_runs','pixel','pixel_invar','pixel_binary','gradient_8dir','cooc','moments_gray_plane'] ["zoom_factor","ratio","width","height","foreground","foreground_grid_9","foreground_grid_16","anisometry","compactness","convexity","moments_region_2nd_invar","moments_region_2nd_rel_invar","moments_region_3rd_invar","moments_central","phi","num_connect","num_holes","projection_horizontal","projection_vertical","projection_horizontal_invar","projection_vertical_invar","chord_histo","num_runs","pixel","pixel_invar","pixel_binary","gradient_8dir","cooc","moments_gray_plane"] ["zoom_factor","ratio","width","height","foreground","foreground_grid_9","foreground_grid_16","anisometry","compactness","convexity","moments_region_2nd_invar","moments_region_2nd_rel_invar","moments_region_3rd_invar","moments_central","phi","num_connect","num_holes","projection_horizontal","projection_vertical","projection_horizontal_invar","projection_vertical_invar","chord_histo","num_runs","pixel","pixel_invar","pixel_binary","gradient_8dir","cooc","moments_gray_plane"] ["zoom_factor","ratio","width","height","foreground","foreground_grid_9","foreground_grid_16","anisometry","compactness","convexity","moments_region_2nd_invar","moments_region_2nd_rel_invar","moments_region_3rd_invar","moments_central","phi","num_connect","num_holes","projection_horizontal","projection_vertical","projection_horizontal_invar","projection_vertical_invar","chord_histo","num_runs","pixel","pixel_invar","pixel_binary","gradient_8dir","cooc","moments_gray_plane"] ["zoom_factor","ratio","width","height","foreground","foreground_grid_9","foreground_grid_16","anisometry","compactness","convexity","moments_region_2nd_invar","moments_region_2nd_rel_invar","moments_region_3rd_invar","moments_central","phi","num_connect","num_holes","projection_horizontal","projection_vertical","projection_horizontal_invar","projection_vertical_invar","chord_histo","num_runs","pixel","pixel_invar","pixel_binary","gradient_8dir","cooc","moments_gray_plane"] ["zoom_factor","ratio","width","height","foreground","foreground_grid_9","foreground_grid_16","anisometry","compactness","convexity","moments_region_2nd_invar","moments_region_2nd_rel_invar","moments_region_3rd_invar","moments_central","phi","num_connect","num_holes","projection_horizontal","projection_vertical","projection_horizontal_invar","projection_vertical_invar","chord_histo","num_runs","pixel","pixel_invar","pixel_binary","gradient_8dir","cooc","moments_gray_plane"]

List of values: 'anisometry'"anisometry""anisometry""anisometry""anisometry""anisometry", 'chord_histo'"chord_histo""chord_histo""chord_histo""chord_histo""chord_histo", 'compactness'"compactness""compactness""compactness""compactness""compactness", 'convexity'"convexity""convexity""convexity""convexity""convexity", 'cooc'"cooc""cooc""cooc""cooc""cooc", 'default'"default""default""default""default""default", 'foreground'"foreground""foreground""foreground""foreground""foreground", 'foreground_grid_16'"foreground_grid_16""foreground_grid_16""foreground_grid_16""foreground_grid_16""foreground_grid_16", 'foreground_grid_9'"foreground_grid_9""foreground_grid_9""foreground_grid_9""foreground_grid_9""foreground_grid_9", 'gradient_8dir'"gradient_8dir""gradient_8dir""gradient_8dir""gradient_8dir""gradient_8dir", 'height'"height""height""height""height""height", 'moments_central'"moments_central""moments_central""moments_central""moments_central""moments_central", 'moments_gray_plane'"moments_gray_plane""moments_gray_plane""moments_gray_plane""moments_gray_plane""moments_gray_plane", 'moments_region_2nd_invar'"moments_region_2nd_invar""moments_region_2nd_invar""moments_region_2nd_invar""moments_region_2nd_invar""moments_region_2nd_invar", 'moments_region_2nd_rel_invar'"moments_region_2nd_rel_invar""moments_region_2nd_rel_invar""moments_region_2nd_rel_invar""moments_region_2nd_rel_invar""moments_region_2nd_rel_invar", 'moments_region_3rd_invar'"moments_region_3rd_invar""moments_region_3rd_invar""moments_region_3rd_invar""moments_region_3rd_invar""moments_region_3rd_invar", 'num_connect'"num_connect""num_connect""num_connect""num_connect""num_connect", 'num_holes'"num_holes""num_holes""num_holes""num_holes""num_holes", 'num_runs'"num_runs""num_runs""num_runs""num_runs""num_runs", 'phi'"phi""phi""phi""phi""phi", 'pixel'"pixel""pixel""pixel""pixel""pixel", 'pixel_binary'"pixel_binary""pixel_binary""pixel_binary""pixel_binary""pixel_binary", 'pixel_invar'"pixel_invar""pixel_invar""pixel_invar""pixel_invar""pixel_invar", 'projection_horizontal'"projection_horizontal""projection_horizontal""projection_horizontal""projection_horizontal""projection_horizontal", 'projection_horizontal_invar'"projection_horizontal_invar""projection_horizontal_invar""projection_horizontal_invar""projection_horizontal_invar""projection_horizontal_invar", 'projection_vertical'"projection_vertical""projection_vertical""projection_vertical""projection_vertical""projection_vertical", 'projection_vertical_invar'"projection_vertical_invar""projection_vertical_invar""projection_vertical_invar""projection_vertical_invar""projection_vertical_invar", 'ratio'"ratio""ratio""ratio""ratio""ratio", 'width'"width""width""width""width""width", 'zoom_factor'"zoom_factor""zoom_factor""zoom_factor""zoom_factor""zoom_factor"

SelectionMethodSelectionMethodSelectionMethodSelectionMethodSelectionMethodselectionMethod (input_control)  string → HTupleHTupleHTupleVARIANTHtuple (string) (string) (HString) (char*) (BSTR) (char*)

Method to perform the selection.

Default value: 'greedy' "greedy" "greedy" "greedy" "greedy" "greedy"

List of values: 'greedy'"greedy""greedy""greedy""greedy""greedy", 'greedy_oscillating'"greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating""greedy_oscillating"

WidthWidthWidthWidthWidthwidth (input_control)  integer → HTupleHTupleHTupleVARIANTHtuple (integer) (int / long) (Hlong) (Hlong) (Hlong) (Hlong)

Width of the rectangle to which the gray values of the segmented character are zoomed.

Default value: 15

HeightHeightHeightHeightHeightheight (input_control)  integer → HTupleHTupleHTupleVARIANTHtuple (integer) (int / long) (Hlong) (Hlong) (Hlong) (Hlong)

Height of the rectangle to which the gray values of the segmented character are zoomed.

Default value: 16

GenParamNameGenParamNameGenParamNameGenParamNameGenParamNamegenParamName (input_control)  string-array → HTupleHTupleHTupleVARIANTHtuple (string) (string) (HString) (char*) (BSTR) (char*)

Names of generic parameters to configure the selection process and the classifier.

Default value: []

List of values: 'gamma'"gamma""gamma""gamma""gamma""gamma", 'nu'"nu""nu""nu""nu""nu"

GenParamValueGenParamValueGenParamValueGenParamValueGenParamValuegenParamValue (input_control)  number-array → HTupleHTupleHTupleVARIANTHtuple (real / integer / string) (double / int / long / string) (double / Hlong / HString) (double / Hlong / char*) (double / Hlong / BSTR) (double / Hlong / char*)

Values of generic parameters to configure the selection process and the classifier.

Default value: []

Suggested values: 'auto'"auto""auto""auto""auto""auto", '0.1'"0.1""0.1""0.1""0.1""0.1", '0.3'"0.3""0.3""0.3""0.3""0.3"

OCRHandleOCRHandleOCRHandleOCRHandleOCRHandleOCRHandle (output_control)  ocr_svm → HOCRSvm, HTupleHTupleHOCRSvm, HTupleHOCRSvmX, VARIANTHtuple (integer) (IntPtr) (Hlong) (Hlong) (Hlong) (Hlong)

Trained OCR-SVM Classifier.

FeatureSetFeatureSetFeatureSetFeatureSetFeatureSetfeatureSet (output_control)  string-array → HTupleHTupleHTupleVARIANTHtuple (string) (string) (HString) (char*) (BSTR) (char*)

Selected feature set, contains only entries from FeatureListFeatureListFeatureListFeatureListFeatureListfeatureList.

ScoreScoreScoreScoreScorescore (output_control)  real-array → HTupleHTupleHTupleVARIANTHtuple (real) (double) (double) (double) (double) (double)

Achieved score using tow-fold cross-validation.

Result

If the parameters are valid, the operator select_feature_set_trainf_svmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmselect_feature_set_trainf_svmSelectFeatureSetTrainfSvmSelectFeatureSetTrainfSvm returns the value 2 (H_MSG_TRUE). If necessary, an exception is raised.

Alternatives

select_feature_set_trainf_mlpselect_feature_set_trainf_mlpSelectFeatureSetTrainfMlpselect_feature_set_trainf_mlpSelectFeatureSetTrainfMlpSelectFeatureSetTrainfMlp, select_feature_set_trainf_knnselect_feature_set_trainf_knnSelectFeatureSetTrainfKnnselect_feature_set_trainf_knnSelectFeatureSetTrainfKnnSelectFeatureSetTrainfKnn, select_feature_set_trainf_mlp_protectedselect_feature_set_trainf_mlp_protectedSelectFeatureSetTrainfMlpProtectedselect_feature_set_trainf_mlp_protectedSelectFeatureSetTrainfMlpProtectedSelectFeatureSetTrainfMlpProtected

See also

select_feature_set_trainf_svm_protectedselect_feature_set_trainf_svm_protectedSelectFeatureSetTrainfSvmProtectedselect_feature_set_trainf_svm_protectedSelectFeatureSetTrainfSvmProtectedSelectFeatureSetTrainfSvmProtected, select_feature_set_svmselect_feature_set_svmSelectFeatureSetSvmselect_feature_set_svmSelectFeatureSetSvmSelectFeatureSetSvm

Module

OCR/OCV

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